1. Field of the Invention
The present invention relates to a paint-removing method, a paint-removing device, and a ship removed of paint.
2. Description of the Related Art
As a paint removing agent, methylene chloride, toluene, chlorotoluene, acetone, ethylene glycol alkyl ether, N-methyl pyrolidone, propylene glycol methyl ether, ethyl-3-etoxypropynate and the like are used.
As a solvent for diluting these paint-removing agents, mineral spirit, methanol, butanol, alkali allyl compounds and the like are used. These substances are mentioned in encyclopedia of Kirk-Othmer Chemical Technology, 17 Vol., 1069 (Wiley Inter Science Publication, New York, 1996). Because paint-removing agents are volatile, paraffin, amine, ethyl amine, sodium hydrate and the like are used to inhibit vaporization of the paint-removing agents.
All the paint-removing agents that have generally been employed are harmful to human bodies and to the environment. Moreover, except for methylene chloride, they cannot be used for powder-baking finish. Thus, there has been a demand for a paint-removing agent and a paint-removing method which are safe, widely applicable and highly effective.
It is thus an object of the present invention to provide a paint-removing method, a paint-removing device and a ship removed of paint by the paint-removing method, which are unharmful to human bodies and to the environment and have a good effect.
The inventors conducted a study of effective paint-removing agents. As a result, they have discovered that when dimethyl sulfoxide is raised at temperature ranging from approximately 35xc2x0 C. to 189xc2x0 C., preferably 40xc2x0 C. to 100xc2x0 C., the dimethyl sulfoxide demonstrates a great paint-removing capability.
In general, dimethyl sulfoxide has a solidification point of 19xc2x0 C. In other words, a so-called room temperature is close to the solidification point of dimethyl sulfoxide. Dimethyl sulfoxide has the feature of completely lacking paint-removing capability nor paint-softening capability at a room temperature.
However, if dimethyl sulfoxide is raised the temperature above mentioned, its paint-removing capability is significantly enhanced. Its paint-removing capability is equal to or even higher than that of powerful methylene chloride. In addition, dimethyl sulfoxide is remarkably safe for human bodies and the environment.
A paint-removing method comprises the steps of putting dimethyl sulfoxide into a tank; raising said dimethyl sulfoxide at a temperature of approximately 35xc2x0 C. to 189xc2x0 C. in the tank; and soaking a member to be removed of paint into said dimethyl sulfoxide in the tank;
A paint-removing method comprises the steps of putting dimethyl sulfoxide into a tank; raising said dimethyl sulfoxide at a temperature of approximately 35xc2x0 C. to 189xc2x0 C.; in the tank; and applying or blowing said dimethyl sulfoxide to a member to be removed of paint.
A paint-removing method comprising the steps of raising dimethyl sulfoxide at a temperature of approximately 35xc2x0 C. to 189xc2x0 C.; and applying or blowing said dimethyl sulfoxide to a member to be removed of paint.
The paint-removing method further comprises raising or keeping said dimethyl sulfoxide at temperature of approximately 35xc2x0 C. to 189xc2x0 C.
A paint-removing method comprises the steps of raising dimethyl sulfoxide at a temperature of approximately 35xc2x0 C. to 189xc2x0 C.; applying or blowing said dimethyl sulfoxide to a member to be removed of paint; and penetrating said dimethyl sulfoxide into pin-holes of a member to be removed of paint.
The heating is performed by radio heating method of high-frequency vibration method.
The paint-removing method further comprises mixing dimethyl sulfoxide with one or more component(s) selected from paint-removing agent, abrasive substance, paint-softening agent, or thickener.
The paint-removing agent is N-methyl pyrrolidone.
The abrasive substance comprises one or more component(s) selected from diaton earth or calcium carbonate.
The paint-softening agent comprises one or more component(s) selected from acetic diethylene glycol monobutyl ether, acetic diethylene glycol ethyl ether, acetic ethylene glycol methyl ether, acetic propylene glycol methyl ether, acetic diethylene glycol alkyl ether, or diethylene glycol dimethyl ether.
The paint-softening agent comprises one or more component(s) selected from diethylene glycol diacetate or ethylene glycol diacetate.
The thickener comprises one or more component(s) selected from methyl cellulose, hydroxy cellulose or polyolefin glycol.
The dimethyl sulfoxide is further mixed with a glycol ether group or a glycol acetate group.
A paint coated on ship body is removed of paint by the paint-removing method.
A paint-removing device comprises a tank containing dimethyl sulfoxide; and heating device which is provided to the tank and which raises said dimethyl sulfoxide at a temperature of approximately 35xc2x0 C. to 189xc2x0 C.
A paint-removing device comprises a tank containing dimethyl sulfoxide; heating device which is provided to the tank and which raises said dimethyl sulfoxide at a temperature of approximately 35xc2x0 C. to 189xc2x0 C.; and an application/blowing device for applying or blowing said dimethyl sulfoxide to a member to be removed of paint.
A paint-removing device comprises heating device which raises dimethyl sulfoxide at a temperature of approximately 35xc2x0 C. to 189xc2x0 C.; and an application/blowing device for applying or blowing said dimethyl sulfoxide to a member to be removed of paint.
The paint-removing device further comprises device for raises or keeping said dimethyl sulfoxide at a temperature of approximately 35xc2x0 C. to 189xc2x0 C.
The heating device is provided with a pipe and/or the application/blowing device which said dimethyl sulfoxide flows.
The heating device is one selected from an electric heater, a flame burner, an infrared ray radiation device, a radio heating device or a high frequency vibration device.
The application/blowing device is a planar or bag-shaped brush.
The brush has an inner surface made from one of threads, non-woven fabric, sponge, or soft flexible rubber.
The inner surface of the brush is provided with a magnet and/or a suction cup.
The brush is provided with an upper liquid-dropping cylinder for causing said dimethyl sulfoxide to flow- down therethrough, an inclined receptacle cylinder for receiving the liquid.